[Chevyfan16]

Yesterday I start my first rebuild, 355 sbc. Everything was going good till it started to make a detonation sound regardless of timing. The temp gauge said 210 but the engine was so hot I couldn't even touch it. It started to puff white smoke out of the right side exhaust pipe. Today I pulled the head an found water in number 7. There is also oil on the runner side of all the intake valves....how do I know I installed the valve seals right? Please help!

[poncho62]

Water in cylinder has nothing to do with valve seals...What does the head gasket and intake gasket look like?

[vinniekq2]

sounds like you have a crack

[Chevyfan16]

Intake gasket looks good, head gasket is hard to tell because it's a steel shim felpro. However during assembly I forgot something and had to take the head off after I had torqued it. After it was all said and done I second guessed myself because the head gasket had been crushed already.

[oldbogie]

Originally Posted by Chevyfan16

Intake gasket looks good, head gasket is hard to tell because it's a steel shim felpro. However during assembly I forgot something and had to take the head off after I had torqued it. After it was all said and done I second guessed myself because the head gasket had been crushed already.

Steel shim gaskets are one time crush and are touchy concerning the flatness and parallelism of the block head deck to the head. They are also touchy to the head bolts actually putting down uniform compression between the parts. The use of torque is a secondary function to what's going on which is bolt stretch that actually holds things together. A lot can go wrong the threads need to be clean and undamaged for both the female portion in the block and the male portion of the fastener. Used bolts should always be greeted with suspicion as if over torqued at some point in their life past the elastic limit they loose strength and will not provide the needed clamping force for an indicated torque value. A bolt that feels mushy around the torque value, that is you get there or close on the wrench but it just seems to keep turning without increasing torque is a good bet it's one of these that has been beyond its stretch limit, something to watch for.

Bolts need to be lubricated and in the case of the Chevy sealed. The OEM torque values are for a motor oil lubricated threads and bottom of the head. The Chevy needs a sealant as well which is a place where plumber's Teflon pipe thread sealant satisfies all these requirements.

Bogie

[Chevyfan16]

I used new ARP bolts with permatex sealer and oil under the heads. I used those head gaskets because it gave me a quench of .035 which is pretty close to perfect. I don't know of any other head gaskets that would give me proper quench.

[zildjian4life218]

Originally Posted by Chevyfan16

I used new ARP bolts with permatex sealer and oil under the heads. I used those head gaskets because it gave me a quench of .035 which is pretty close to perfect. I don't know of any other head gaskets that would give me proper quench.

The steel shims gaskets usually have a minimum rma surface finish. I was always told to use copper head gasket spray with them. Hopefully you didn't hurry anything and can replace them and be on your way.

[Chevyfan16]

I used the copper spray... I ordered another one and will install it as long as nothing's warped! But I still don't know why the engine got so hot. Couldn't even touch the valve covers.

[68NovaSS]

Originally Posted by Chevyfan16

But I still don't know why the engine got so hot. Couldn't even touch the valve covers.

Did you refill the radiator after the thermostat opened, and burp it? You could have a air lock.

[4inthefloor]

i dont know what you have this 355 in but if its a custom set up and the rad cap isnt the highest point of the cooling system you'll get air trapped in the intake and youll have to but a bleed valve in the thermostat housing and force you coolant in to the rad once you have it topped off. i use a old 2 lieter bottle

[Chevyfan16]

It started over flowing out the radiator so I put the cap on....it sucked a lot out of the over flow bottle. I really thought it was an air pocket like you said, but I didn't know how to figure out if it was an air pocket or not.

[4inthefloor]

put a secound temp sensor in the intake or thermostat houseing,, if your temps vary you probally have a air pocket.....you need to leave the cap off untill its up to operateing temp and the thermostat opens... it will just about empty the rad when it opens

[Chevyfan16]

Okay right now I'm just really hoping nothing is warped!!

[4inthefloor]

you running cast or alum heads? if there cast your probally fine,,, if u have alum heads on a cast block you need to put a straight edge across the head and see if everything looks kosher. cast and alum disapate heat at different rates and it makes it faily easy to warp alum heads on a cast block. also, make sure you have antifreeze in the motor even cranking for break in becasue antifreeze brings down the boiling point of your coolant

[Chevyfan16]

Cast heads!! And I'll be sure to put coolant in and not just water....do you think a 195 thermostat is okay? Thank you very much!